Learn more about Arthur Jensen
Arthur Jensen (born August 24 1923) is a Professor Emeritus of educational psychology at the University of California, Berkeley. Jensen is known for his work in psychometrics and differential psychology, which is concerned with how and why individuals differ behaviorally from one another. He is a major proponent of the hereditarian position in the nature versus nurture debate, the position that concludes genetics play a significant role in behavioral traits, such as intelligence and personality. He is the author of over 400 scientific papers published in refereed journals<ref>Sailer 1998</ref> and currently sits on the editorial boards of the scientific journals Intelligence and Personality and Individual Differences.<ref>Intelligence and Personality and Individual Differences publisher's pages.</ref>
Jensen is both among the most eminent psychologists of the twentieth century<ref>Jensen is listed in a study by Haggblom et al. (2002),  of the 100 most eminent psychologists of the twentieth century, at number 47.</ref> and a highly controversial figure. A special 1998 issue of the scientific journal Intelligence was entirely devoted to his life and work under the headline “A King among Men”. E. O. Wilson calls him “an honest and courageous man”.<ref>Cover of Intelligence, Race and Genetics (Miele 2002).</ref> A lifelong student of Mahatma Gandhi, Jensen once offered this insight during an interview
- "One of the tenets of my own philosophy is to be as open as possible and to strive for a perfect consistency between my thoughts, both spoken and published, in their private and public expression. This is essentially a Gandhian principle, one that I have long considered worth striving to live by."
Jensen was born August 24, 1923, to a mother of Polish Jewish and German ancestry and a father of Danish ancestry.<ref>Miele 2002</ref> Jensen studied at University of California, Berkeley (B.A. 1945), San Diego State College (M.A., 1952) and Columbia University (Ph.D., 1956). Jensen did his doctoral thesis on the Thematic Apperception Test. From 1956 through 1958, Jensen did his postdoctoral research at the University of London, Institute of Psychiatry. Upon returning to the United States, Jensen became a researcher and professor at the University of California, Berkley, where he focused on individual differences in learning, especially the influences of culture, development, and genetics on intelligence and learning. Jensen received tenure at Berkeley in 1962 and was given his first sabbatical in 1964. He has concentrated much of his work on the learning difficulties of culturally disadvantaged students. In 2003, Jensen was awarded the Kistler Prize for original contributions to the understanding of the connection between the human genome and human society.
Jensen has had a life long interest in classical music and was, early in his life, attracted by the idea of becoming a conductor himself. At fourteen, Jensen conducted a band that won a nationwide contest held in San Francisco. Later, Jensen conducted orchestras and attended a seminar given by Nikolai Sokoloff. Soon after graduating from Berkeley, Jensen moved to New York, mainly to be near the conductor Arturo Toscanini. Jensen was also deeply interested in the life and example of Gandhi, producing an unpublished book-length manuscript on his life. During Jensen's period in San Diego he spent time working as a social worker with the San Diego Department of Public Welfare.
 IQ and academic achievement
Jensen's interest in learning differences directed him to the extensive testing of black, Mexican-American, and other minority-group school children. The results led him to distinguish between two separate types of learning ability. Level I, or associative learning, may be defined as retention of input and rote memorization of simple facts and skills. Level II, or conceptual learning, is roughly equivalent to the ability to manipulate and transform inputs, that is, the ability to solve problems. Statistical analysis of his findings led Jensen to conclude that Level I abilities were distributed equally among members of all races, but that Level II occurred with significantly greater frequency among whites and Asian-Americans than among African-Americans and Mexican-Americans.
Later, Jensen was an important advocate in the mainstream acceptance of general intelligence factor, a concept which was essentially synonymous with his Level II conceptual learning. General intelligence factor, or g, is an abstraction that stems from the observation that scores on all forms of cognitive tests correlate positively with one another.
Jensen's most controversial work, published in February 1969 in the Harvard Educational Review, was titled "How Much Can We Boost I.Q. and Scholastic Achievement?" It concluded, among other things, that "head start" programs designed to boost African-American IQ scores had failed, and that this was likely never to be remedied, largely because, in Jensen's estimation, heritability of IQ was over 0.7 of the within-race IQ variability, and the 0.3 left over was due to non-shared environmental influences.
The work became one of - if not the most - cited papers in the history of psychometrics,<ref>While only limited inference can be drawn from citation analysis, the paper has received over 1262 citations according to the ISI citation index (Aug. 2006), compared with the other influential figures in the area, Hans J. Eysenck's 821 citations of "A Revised Version of the Psychoticism Scale" (1987; lead author Eysenck, S. B.G.), Charles Spearman's 644 of "General Intelligence Objectively Determined and Measured" (1904), James Flynn's 402 citations of "Massive IQ gains in 14 Nations - What IQ Tests Really Measure" (1987), J. Phillipe Rushton's 394 of "Behavioral-Development and Construct-Validity: the Principle of Aggregation" (1983; lead author with Brainderd C. J., Pressley M.), "Linda Gottfredson's 358 of "Circumscription and Compromise: A Developmental Theory of Occupational Aspirations" (1981), and Robert J. Sternberg's 239 of "People's Conceptions of Intelligence" (1981; lead author with Conway, BE, Ketron, JL, et al.).</ref> and saw students and faculty stage large protests outside Jensen's U.C. Berkeley office, as well as the issuing of death threats against him. Jensen was denied reprints of his work by his publisher and was not permitted to reply in response to letters of criticism -- both extremely unusual and exceptional policies for their day. Many colleagues at the time felt that even if Jensen's work contained no scientific merit, his treatment was itself against the spirit of science and the free exchange of ideas.
In a later article, Jensen argued that his claims had been misunderstood:
- ...nowhere have I "claimed" an "innate deficiency" of intelligence in blacks. My position on this question is clearly spelled out in my most recent book: "The plain fact is that at present there exists no scientifically satisfactory explanation for the differences between the IQ distributions in the black and white populations. The only genuine consensus among well-informed scientists on this topic is that the cause of the difference remains an open question" (Jensen, 1981a, p. 213).
Thomas Sowell wrote:
- Professor Jensen pointed out back in 1969 that black children's IQ scores rose by 8 to 10 points after he met with them informally in a play room and then tested them again after they were more relaxed around him. He did this because "I felt these children were really brighter than their IQ would indicate." What a shame that others seem to have less confidence in black children than Professor Jensen has had. 
However, Jensen's 1998 The g Factor: The Science of Mental Ability gives his position suggesting a genetic component is implicated in the white-black difference in IQ:
- In Chapter 12: Population Differences in g: Causal Hypotheses, Jensen writes: "The relationship of the g factor to a number of biological variables and its relationship to the size of the white-black differences on various cognitive tests (i.e., Spearman's hypothesis) suggests that the average white-black difference in g has a biological component. Human races are viewed not as discrete, or Platonic, categories, but rather as breeding populations that, as a result of natural selection, have come to differ statistically in the relative frequencies of many polymorphic genes. The genetic distances between various populations form a continuous variable that can be measured in terms of differences in gene frequencies. Racial populations differ in many genetic characteristics, some of which, such as brain size, have behavioral and psychometric correlates, particularly g."
In 1994 he was one of 52 signatories on "Mainstream Science on Intelligence," an editorial written by Linda Gottfredson and published in the Wall Street Journal, which defended the findings on race and intelligence in The Bell Curve.
In 1995 an American Psychological Association task force published a paper titled "Intelligence: Knowns and Unknowns" which concluded that within the white population the heritability of IQ is "around .75" <ref>Template:Cite web</ref>
 Gould's criticism
Gould claims that Jensen misapplies the concept of "heritability", which Gould defines as a measure of the variation of a trait due to inheritance within a population (Gould 1981: 127; 156-156). Jensen, Gould claims, uses heritability to measure differences between populations.
Second, Gould disagrees with Jensen's belief that IQ tests measure a real variable, g, or "the general factor common to a large number of cognitive abilities" which can be measured along a unilinear scale. This is a claim most closely identified with Charles Spearman. According to Gould, Jensen misunderstood the research of L. L. Thurstone to ultimately support this claim; Gould however argues that Thurstone's factor analysis of intelligence revealed g to be an illusion (1981: 159; 13-314).
In a 1982 review of The Mismeasure of Man, Jensen gives point-by-point rebuttals to Gould's critique, including Gould's treatment of heritability, the "reification" of g, and the use of Thurstone's analysis. Gould's responses appear in the 1996 edition of The Mismeasure of Man.
 Jensen's response and criticism
In Arthur Jensen's response to Gould's criticisms, in the paper titled The Debunking of Scientific Fossils and Straw Persons., Jensen begins his paper with this observation
- "Stephen Jay Gould is a paleontologist at Harvard's Museum of Comparative Zoology and offers a course at Harvard entitled, "Biology as a Social Weapon." Apparently the course covers much the same content as does the present book. Having had some personal cause for interest in ideologically motivated attacks on biologically oriented behavioral scientists, I first took notice of Gould when he played a prominent role in a group called Science for the People and in that group's attack on the theories of Harvard zoologist Edward O. Wilson, a leader in the development of sociobiology..."
Jensen adds that Gould made a number of misrepresentations, whether intentional or unintentional, while purporting to present Jensen's own positions
- "In his references to my own work, Gould includes at least nine citations that involve more than just an expression of Gould's opinion; in these citations Gould purportedly paraphrases my views. Yet in eight of the nine cases, Gould's representation of these views is false, misleading, or grossly caricatured. Nonspecialists could have no way of knowing any of this without reading the cited sources. While an author can occasionally make an inadvertent mistake in paraphrasing another, it appears Gould's paraphrases are consistently slanted to serve his own message."
 Recent books
 The g Factor
The g Factor: The Science of Mental Ability (1998) is considered by supporters to be Jensen's magnum opus on the general intelligence factor (g). The book deals with the intellectual history of the discovery of g and various models of how to conceptualize intelligence, and with the biological correlates of g, its heritability, and its practical predictive power.
 Clocking the Mind
Jensen's forthcoming Clocking the Mind : Mental Chronometry and Individual Differences (July 17, 2006) is the culmination of 25 years of researching mental chronometry (MC), a variety of techniques for measuring the speed with which the brain processes information. Whereas IQ merely represents an ordinal (ranking) scale and thus possesses no true scale properties, Jensen argues mental chronometry represents a true natural science of mental ability.
 Further reading
- SASP Interviews: Arthur R. Jensen. Beaujean, A. A. (2002, July). SASP News, 2 (4). (pdf)
- "A Conversation With Arthur Jensen (Part 2". (1992). American Renaissance, 3(9).
- Intelligence, Race, and Genetics: Conversations with Arthur R. Jensen. (2002) Frank Miele (of Skeptic Magazine). Westview Press. ISBN 0-8133-4008-X
 Selected Articles, Books, & Book Chapters
- Rushton, J. P., & Jensen, A. R.. (2005). Thirty years of research on Black-White differences in cognitive ability. Psychology, Public Policy, & the Law, 11, 235-294. (pdf)
- Rushton, J. P., & Jensen, A. R. (2005). Wanted: More race-realism, less moralistic fallacy. Psychology, Public Policy, and Law, 11, 328-336. (pdf)
- Rushton, J. P., & Jensen, A. R. (2003). African-White IQ differences from Zimbabwe on the Wechsler Intelligence Scale for Children-Revised are mainly on the g factor. Personality and Individual Differences, 34, 177-183. (pdf)
- Jensen, A. R. (2002). Galton's legacy to research on intelligence. Journal of Biosocial Science, 34, 145-172.
- Jensen, A. R. (2002). Psychometric g: Definition and substantiation. In R. J. Sternberg, & E. L. Grigorenko (Eds.). The general factor of intelligence: How general is it? (pp. 39-53). Mahwah, NJ, US: Lawrence Erlbaum.
- Jensen, A. R. (2000). Testing: The dilemma of group differences. Psychology, Public Policy, & Law, 6, 121-128.
- Jensen, A. R. (1998) The g factor and the design of education. In R. J. Sternberg & W. M. Williams (Eds.), Intelligence, instruction, and assessment: Theory into practice. (pp. 111-131). Mahwah, NJ: Lawrence Erlbaum.
- Jensen, A. R. (1996). Giftedness and genius: Crucial differences. In C. P. Benbow, & D. J. Lubinski (Eds), Intellectual talent: Psychometric and social issues (pp. 393-411). Baltimore: Johns Hopkins University.
- Jensen, A. R. (1995). Psychological research on race differences. American Psychologist, 50, 41-42.
- Jensen, A. R. (1993). Spearman's g: Links between psychometrics and biology. In F. M. Crinella, & J. Yu (Eds.), Brain mechanisms: Papers in memory of Robert Thompson (pp. 103-129). New York: Annals of the New York Academy of Sciences.
- Jensen, A. R. (1993). Why is reaction time correlated with psychometric g? Current Directions in Psychological Science, 2, 53-56.
- Jensen, A. R. (1989). The relationship between learning and intelligence. Learning and Individual Differences, 1, 37-62.
- Kranzler, J. H., & Jensen, A. R.(1989). Inspection time and intelligence: A meta-analysis. Intelligence, 13, 329-347.
- Jensen, A. R. (1974). Ethnicity and scholastic achievement. Psychological Reports, 34, 659-668.
- Jensen, A. R. (1974). Kinship correlations reported by Sir Cyril Burt. Behavior Genetics, 4, 1-28.
 External links
- The London School of Differential Psychology: Arthur R. Jensen
- Powerpoint presentation of Jensen's biography
- Jensen's Response to Gould's Criticisms
- Article about Jensen and the History of IQ testingda:Arthur Jensen (psykolog)